Mechanical hooks are mechanical tools, which are designed to transmit loads concentrated to a relatively small area. Also, mechanical hooks are used to carry bulky objects by hanging on a small portion of such objects. Mechanical hooks may take several shapes and design forms. In one common form, they have a relatively large open loop on one end and a smaller closed loop on the other end connected with a relatively straight portion. The larger open loop is used to carry or hang on the bulky object and the smaller closed loop is used to transmit the load to the desired mechanism or other load bearing structures. One example of such a mechanical hook is a fishhook.
A critical aspect of the mechanical loop is its load carrying capacity and its ability to retain its structural shape and durability when subjected to such loads. For example, in the case of fishhook, the open loop needs to retain its shape without substantially opening, which otherwise may lead to dropping the caught fish.
In certain hook designs, the shape of the open (or closed loop) may have precise forms, such as a sharpened tip with certain conical angles, such as ones common in fishhooks. The durability and preservation of these critical shapes may become important in ensuring that it serve its intended function. Accordingly, the application of loads to the hook should not lead to a degradation of such design features whether in the form of substantial elastic or plastic deformation. As a result, it is desirable that mechanical hooks have very high strength characteristics to resist such substantial deformations.
Mechanical hooks are also frequently used in various corrosive environments, such as the marine environment, as in the case of a fishhook, and as such they should be corrosion resistant and preferably should preclude any galvanic corrosion with other materials they come into contact with.
Mechanical hooks, such as fishhooks, are commonly made by a method which utilizes a standard wire product as feedstock input material. The feedstock wire material is then subsequently subjected to several progressive forming operations, such as bending, forging, machining, grinding etc, which leads to the final form. Although, the wire feedstock alloy can provide a high strength alloy, its initial form severely limits the design flexibility, such as the form of cross section of the hook. Therefore, the beneficial use of geometric effects for high load carrying capacities cannot be utilized. Although, various casting processes can be utilized to make mechanical hooks, the availability of high strength alloys are limited, and the cast hooks are generally considered to be of inferior quality.
Accordingly, a need exists for a novel material in the use of mechanical hooks and methods of making such hooks that provides high strength, design flexibility and low cost manufacturing.